The present invention pertains to a process for feeding paper rolls to web-fed rotary presses in which each paper roll is brought to a main roll stock room used for long-term storage to a roll stand of the web-fed rotary press by means of a paper roll conveying system and to a device for carrying out such a process.
The supply of the web-fed rotary presses with paper rolls must be planned very carefully in order to feed the correct paper rolls to the roll stands at a given time. This is especially true in newspaper printing shops. High requirements in terms of reliability, safety, and economics are imposed on the organization of the corresponding "roll cellar". In addition, especially the weight of such a paper roll, the time pressure, and the basic requirement that each edition must be published completely and in time must be taken into account.
It is now a common practice to supply web-fed rotary presses with paper rolls so that, e.g., in the case of a daily paper, the paper rolls are deposited during the day in predetermined places in a so-called intermediate roll stockroom. The paper rolls are then brought, during the night, when printing is carried out, to the roll stands, using, if needed, material handling means, e.g., a track-bound cart. At the roll stand, the rolls are unpacked and prepared manually for automatic bonding. For economic reasons, special unpacking and bonding area preparation stations are currently increasingly arranged in front of the roll stands. The replacement of the nearly used-up roll with the fresh roll, as well as the bonding and consequently the adaptation of the new . paper roll fed into the paper web, which passes through the web-fed rotary press, are carried out in the roll stand itself. The residual roll that is nearly used up is removed from the roll stand and disposed of. To avoid blocking of the supply routes, a separate disposal route is usually provided.
In the roll cellar systems described previously, trouble-free operation of the web-fed rotary presses depends especially on the quality of the manual work performed by an operator. Errors made by the operator during the feeding in or the preparation of bonding areas can lead to rather long downtimes. In addition, the handling of the heavy paper rolls can be associated with relatively heavy physical strain.
An automatic roll cellar was therefore designed and put into operation at the Tokyo daily ASAHI SHIMBUN. The basic requirement is, however, to make the roll size and the paper grade uniform, i.e., only paper rolls of one size with identical packaging are processed.
This roll cellar system will be explained on the basis of FIG. 1 below.
The roll cellar shown in FIG. 1 has a main stockroom A, an auxiliary stockroom B, and a roll stand room C. In this roll cellar system, identical paper rolls P are conveyed via a feed station 1 and a freight elevator 2 from a road-level paper roll receiving station into the roll cellar and are fed into the main stockroom A via a conveyor belt 3. Turntables 4, which serve to adjust the direction of rolling, are provided along the conveyor belt 3. The paper rolls P are pushed off the conveyor belt 3 with pushing devices 5 and are thus loaded into the sloping main stockroom A. Said main stockroom A has oblique guide tracks with buffer members 6, which are provided to decelerate the paper rolls P rolling off. The buffer members 6 are arranged at defined spaced locations. A second conveyor belt 3' brings the paper rolls to a loading station 7 as needed, where unmanned material handling vehicles 7a (AGVs) are automatically loaded with the paper rolls. The unmanned material handling vehicles 7a with the rolls travel in a loop along a path defined by a guide loop 8 through the entire roll stand room C in order to unload the needed paper rolls P at a web-fed rotary press to be supplied. Both the unpacking and the bonding area preparation are performed by robots. The disposal of the roll remnants 9 from the roll stands is also performed automatically by robots 9a.
Because the material handling vehicles 7a are able to travel in one direction only, there are long travel times and a large space is required. In addition, because of the preparation robots used, this system can be used only if the paper roll size is uniform and the packaging is identical. This system is unsuitable for a printing shop outfitted according to European standards, where different roll widths and roll diameters as well as different paper grades are used.
Furthermore, no controlled emergency operation is possible with this roll cellar system, partly because the conveying distances that must be traveled with the unmanned transport carts are very long and partly because the personnel have no experience with the steering of the loaded and empty unmanned material handling vehicles. Malfunctions would inevitably lead to a greatly reduced press run or to stoppage of the printing operation. Finally, the main stockroom A is able to work only according to the "first in first out" principle.